A cluster-randomized trial of the school-based ‘Superprotegidas’ behavioral intervention to improve HPV vaccination uptake in Colombian girls

PURPOSE: This study evaluated the effect of Superprotegidas, a behavioral intervention designed to increase HPV vaccination rates among girls and their caregivers in a Colombian municipality, following the Phase III framework of the ORBIT Model for Behavioral Treatment Development. METHODS: A two-arm randomized clinical trial was conducted with schools as the unit of randomization. The intervention, based on the Capability-Opportunity-Motivation-Behavior model (COMB), included a pedagogical workshop for girls, a letter, an open chat, multimedia messages, and parental reminders. RESULTS: A total of 77 girl-caregiver pairs (154 participants; girls aged 9-14) were enrolled: 42 pairs in the intervention group and 35 in the control group. Post-intervention vaccination rates were significantly higher in the intervention group (52.4%) compared to the control group (28.6%) (OR, 2.75 [95% CI: 1.06-7.12]). Predictors of vaccination, in addition to intervention participation, included lower girl's school level and higher scores on several behavioral drivers of the COM-B model (awareness of vaccine efficacy against cancer, awareness of vaccine safety, vaccine availability in schools, reflective motivation for cancer prevention, and automatic motivation related to vaccine advantages) as well as higher caregiver's self-efficacy. CONCLUSIONS: The findings suggest that the Superprotegidas program increased HPV vaccination rates among age-eligible girls. As the program was implemented with existing program resources, and the findings also suggest that the program could be implemented in similar school-based settings.